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排序方式: 共有162条查询结果,搜索用时 11 毫秒
71.
The British Equine Veterinary Association (BEVA) was established in 1961 and launched the Equine Veterinary Journal (EVJ) in 1968. This review outlines some of the major advances in equine science and practice that have occurred in that time and the role played by the Journal in facilitating those developments. 相似文献
72.
Silver PG Beck SL Wallace TC Meade C Myers SC James DE Kuehnel R 《Science (New York, N.Y.)》1995,268(5207):69-73
The M(w) = 8.3 deep (636 kilometers) Bolivian earthquake of 9 June 1994 was the largest deep-focus earthquake ever recorded. Seismic data from permanent stations plus portable instruments in South America show that rupture occurred on a horizontal plane and extended at least 30 by 50 kilometers. Rupture proceeded at 1 to 3 kilometers per second along the down-dip azimuth of the slab and penetrated through more than a third of the slab thickness. This extent is more than three times that expected for a metastable wedge of olivine at the core of the slab, and thus appears to be incompatible with an origin by transformational faulting. These large events may instead represent slip on preserved zones of weakness established in oceanic lithosphere at the Earth's surface. 相似文献
73.
Global-scale similarities in nitrogen release patterns during long-term decomposition 总被引:2,自引:0,他引:2
Parton W Silver WL Burke IC Grassens L Harmon ME Currie WS King JY Adair EC Brandt LA Hart SC Fasth B 《Science (New York, N.Y.)》2007,315(5810):361-364
Litter decomposition provides the primary source of mineral nitrogen (N) for biological activity in most terrestrial ecosystems. A 10-year decomposition experiment in 21 sites from seven biomes found that net N release from leaf litter is dominantly driven by the initial tissue N concentration and mass remaining regardless of climate, edaphic conditions, or biota. Arid grasslands exposed to high ultraviolet radiation were an exception, where net N release was insensitive to initial N. Roots released N linearly with decomposition and exhibited little net N immobilization. We suggest that fundamental constraints on decomposer physiologies lead to predictable global-scale patterns in net N release during decomposition. 相似文献
74.
A hydrophobic transmembrane segment at the carboxyl terminus of thy-1 总被引:12,自引:0,他引:12
T Seki H C Chang T Moriuchi R Denome H Ploegh J Silver 《Science (New York, N.Y.)》1985,227(4687):649-651
The mode of integration of the glycoprotein thy-1 within the cell membrane has been controversial due to an apparent lack of a transmembrane hydrophobic segment. Rat and mouse complementary DNA and genomic clones encoding the thy-1 molecule have been isolated and sequenced. These studies have enabled us to determine the intron-exon organization of the thy-1 gene. Furthermore, they have revealed the existence of a sequence which would encode an extra segment (31 amino acids) at the carboxyl terminus of the thy-1 molecule. These extra amino acids include a 20-amino acid hydrophobic segment which may be responsible for integration of thy-1 within the plasma membrane. 相似文献
75.
76.
Silver EA 《Science (New York, N.Y.)》1969,166(3910):1265-1266
The presence of magnetic anomaly 3, age 5 million years, beneath the continental slope off northernmost California, is evidence for underthrusting of the continental margin during the late Cenozoic. Folded and faulted strata near the base of the slope attest to deformation of the eastern edge of the turbidite sedimzents in the Gorda Basin; the deformation observed is exactly that expected from underthrusting. The relative motions of three crustal plates also suggest underthrusting, possibly with a major component of right-lateral slip. 相似文献
77.
Nitrogen fixation, apparently by bacterial endosymbionts, is associated with intertwining chains of two species of the diatom Rhizosolenia. In situ fixation rates were enhanced by incubation in the dark, whereas concurrent shipboard experiments either underestimated or did not detect nitrogen fixation. This is the first example of nitrogen fixation associated with a bacteria-diatom symbiosis in the pelagic zone, and it indicates that these systems may contribute a significant amount of "new" nitrogen to oligotrophic waters. 相似文献
78.
The rules of nucleic acid base-pairing have been used to construct nanoscale architectures and organize biomolecules, but little has been done to apply this technology in vivo. We designed and assembled multidimensional RNA structures and used them as scaffolds for the spatial organization of bacterial metabolism. Engineered RNA modules were assembled into discrete, one-dimensional, and two-dimensional scaffolds with distinct protein-docking sites and used to control the spatial organization of a hydrogen-producing pathway. We increased hydrogen output as a function of scaffold architecture. Rationally designed RNA assemblies can thus be used to construct functional architectures in vivo. 相似文献
79.
Kristen Parker Elisabeth Snead James Anthony Tawni Silver 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(8):748-752
Blastomycosis is one of the most common systemic fungal infections in dogs in North America Pulmonary manifestations are most common; localized disease is rare. A case of localized oronasal blastomycosis mimicking oral neoplasia is described. Long-term therapy with itraconazole resulted in clinical cure. 相似文献
80.
KM Neil JE Axon AP Begg PG Todhunter PL Adams AE Fine JP Caron AR Adkins 《Australian veterinary journal》2010,88(1-2):4-12
Objective To determine the clinical characteristics, short-term outcome and future athletic performance of foals with septic osteomyelitis.
Design Retrospective clinical study of 108 Thoroughbred foals with radiographic evidence of bone infection that were presented at the Scone Veterinary Hospital between August 1995 and December 2001. Medical records were reviewed and information concerning signalment, the clinical, laboratory and radiographic findings, treatment and outcome was obtained. Racing records were obtained and evaluated for surviving foals that had reached racing age.
Results Mean age of foals at initial evaluation was 39 days (range 1–180 days); 21 foals had multiple radiographic bone lesions (19.4%), and 76 had concurrent septic arthritis (70.4%). The most frequently affected bones were the femur, tibia and distal phalanx. In total, 87 foals were discharged from the hospital (80.6%), 79 survived long-term to reach racing age and 52 raced (65.8%). Overall, 48% (52/108) of the foals treated for osteomyelitis raced. Foals less than 30 days of age at the time of diagnosis, critically ill foals and those with multiple bones or joints affected were significantly less likely to be discharged from hospital. Multiple septic joints, but not multiple bone involvement, had an unfavourable prognosis for racing.
Conclusions The prognosis for survival of foals with septic osteomyelitis or osteitis is favourable. Multiple bone or joint involvement is an important short-term prognostic indicator; however, the involvement of multiple joints, but not multiple infected bones, is associated with an unfavourable prognosis for racing. 相似文献
Design Retrospective clinical study of 108 Thoroughbred foals with radiographic evidence of bone infection that were presented at the Scone Veterinary Hospital between August 1995 and December 2001. Medical records were reviewed and information concerning signalment, the clinical, laboratory and radiographic findings, treatment and outcome was obtained. Racing records were obtained and evaluated for surviving foals that had reached racing age.
Results Mean age of foals at initial evaluation was 39 days (range 1–180 days); 21 foals had multiple radiographic bone lesions (19.4%), and 76 had concurrent septic arthritis (70.4%). The most frequently affected bones were the femur, tibia and distal phalanx. In total, 87 foals were discharged from the hospital (80.6%), 79 survived long-term to reach racing age and 52 raced (65.8%). Overall, 48% (52/108) of the foals treated for osteomyelitis raced. Foals less than 30 days of age at the time of diagnosis, critically ill foals and those with multiple bones or joints affected were significantly less likely to be discharged from hospital. Multiple septic joints, but not multiple bone involvement, had an unfavourable prognosis for racing.
Conclusions The prognosis for survival of foals with septic osteomyelitis or osteitis is favourable. Multiple bone or joint involvement is an important short-term prognostic indicator; however, the involvement of multiple joints, but not multiple infected bones, is associated with an unfavourable prognosis for racing. 相似文献